Automatic door latch release system



May 30, 1950 M. L.. THOMAS, SR.. ETAL.

AUTOMATIC DOOR LATCH RELEASE SYSTEM 2 Sheets-Sheet 1 Filed March 26, 1948 MW 3U, 195.0 M. A.. THOMAS, SR., ET AL 2,509,542

AUTOMATIC DooR LATCH RELEASE SYSTEM 2 Sheets-Sheet 2 ma .l

TTRNEK Patented May 30, 195i) UNITEDV STATES TENT OFFICE AUTOMATIC DUUR LATCH RELEASE SYSTEME Application-March 26, 1948, Serial N o. 17,176

This invention relates to an automatic door latch release system, andi particularly to such a system in which the opening of one door causes release of a latch on asecond door, and vice versa,

The main object is to provide a pair of doors for` a bath room which individually have locks or latches, for example,` with a two-Way automatic system for releasing the lock or latch of one door when the other door is opened, so that both doors are automatically opened by merely opening one of the two.

Another important Objectis to provide one of a pair of doors for a room with al special latch; and the other door with a latch-releasing device operated by opening the latter door and con# nected to the special latch on the first-mentioned door in such manner as to open the special latch upon being thus operated.

An ancillary object is to provide each of a groupof doors for a roonr with a latch and an operating device,` with the operating device on; one door connected to the latch on` each` other door.

A further object is to have a twoevvay latchreleasing system as indicated which provides= for individual and independent locking or latching each of the twooloors without interference from' the releasing systenfi,4 but instead automatically setting the latter for operation.

It is also an object to" have such a two-way latching-releasing system which is simple to install and so simple tof operate that it requires substantially no attention and is virtually automatic at all times.

Other objects and advantages will be disclosed` in greater detail as the subjoined specication proceeds. i

As it is desired to bring out comprehensively the `features of the invention to enable a` p"ei`^so"n"4 skilled in the art to rnakeand usethelatten it is illustrated in the accompanying drawings forming4 part hereof, an'din` which:

Figure 1 is a side elevationof a` pair`of'- doors of a bath room, for example, on alV greatly 1` -M duced scale, including an automatici two" latch and latchereleasing system made according?? to the invention and embodying the latter in* practical form;

Figure 2 is an enlarged" iragnrientaryVA section of- 2 of the present invention shown partly in section to disclose structural details;

Figure 5 is a section of the latch taken on line 5-5 in Figure 4.

In the live iigures, the same reference numerals indicate the same or identical parts.

When a room has two doors, as for example a bath room, it isV quite obvious that lboth doors are necessarily latched or locked when the room is occupied, but that it is quite as obvious that when the occupant leaves this room, he should unlock both doors and not only the one door through which he leaves the" room. However, it happens all too often that this point is ior` gotten, and only the door used to leave the room" is unlocked, while theother door remains locked, making it necessary for a person attempting to enter the room through the latter to go around through other rooms to reach the open door. This, of course, is most annoying andA often inconvenient,` and nonetheless Wholly unnecessary according to the present invention, as Will immediately be explained in full detail.

Hence, in the practice of our invention, and

"1 referring now again to the drawings, a pair of mutually-independent doors 5, l, are respectively hinged at 8, 8, 9 to the door frames lil, l I` in wall i2 of a bath room or the like, and provided with more or less conventional door `knobs' I3, lLl and associated locks l5 and I6 ad-` jacent door jambs il and I8, respectively, of the door frames. The details of the last-mentioned locks form no part ofthe invention, and, there=` fore, require no further discussion.

However, on door jam-b il, a special latch or holt casing le issecured in place by screws; nails or the likev 2Q, 2li and has a bolt 2i adapted to be extended into locking relation in socket 22 of door 6 to lock the latter. The mentioned socket is securedin place=by screws 23, or the like, in the door (Figure e). Astud Eil` upon' the latch provides means for manually operating this latch or holt` by pushingthe operating stud' to the right in longitudinal slot 25 untlildependingportion 26 oithisslotis reached, as indicated at 21 in broken lines',` when the stud may loepulled down into this depending portion; preventing` In aA i spring 29 held at the inner end by awasher 3B" fixed in place by `ascrew 3l screwed into end"32 of casing I9; and at the other endl the springifs`y` latch casingoutM of contactwiththedoor socket? Obviously, when the stud 2d is drawn down into slot portion 2t, the latch bolt 2i is partly rotated in latch casing le so that when it is rotated back again Lby any means to register the stud with slot 25, spring 2Q will instantly return the bolt from the position indicated in broken lines at Sli into casing le so that the stud again occupies its initial idle withdrawn position as shown in Figures l and 5. As will shortly appear, the head 35 of stud 2d has an eye Sii to which a cord or the like 3l is attached by which to release the latch or bolt just described.

In connection with the other door jamb it (Figures 2 and 3) is an operating frame 33 fixed in position by screws or other means (not shown), with a block Sil held in place thereon by a pair oi pins ll, fili and having an inner upwardly-projecting spring post secured by attaching screws il? to the frame, while screws 43 attach the frame by its inner lugs to the inner wall iii of door jamb lil. Projecting a distance into block 39 is a horizontal shaft 1lb having a circumferential groove having a rectangular cross-section into wl" a retaining screw i3 projects in order to prevent longitudinal shifting or the shaft during rotation, this shaft extending inwardly to the right and terminating in a bearing or pillow block il secured on frame 3&3 by screws d2 and serving as a spring post for a spring id mounted on the shaft whose purpose will shortly be explained. Fixed on the latter is a small bevel gear oil with the bevel teeth 5i thereof meshing with the teeth 52 of a relatively large bevel gear 53 rotatably mounted upon the vertical stud shaft 5d projecting upward from stationary block 3Q to which it may be suitably secured. The hub 55 of gear 33 is retained rotatably in assembled relation with stud shaft 52 by means oi screw while above the bevel teeth is a large spur gear 5l with spur teeth 38 exposed adjacent to door l in a horizontal slot 59 in outer wall 553 of jamb i3 and meshing with the teeth Si of an arcuate rack 32 on the edge 63 of door i and having the end lugs lili thereof Secured to the door by screws Thus, when the door is opened in the direction indicated by arrow QS in Figure 3, rack b2 will cause corresponding limited rotation of spur gear 5l and bevel gear 53 beneath it in the direction of arrow 6l until the teeth di of the rack are brought out of contact with teeth 5t? of the spur gear, the rotation being suicient to cause substantially a complete revolution of smaller bevel gear Eid with its shaft d'5.

Upon this horizontal shaft is mounted a slidable collar provided at its outer end with clutch teeth normally engaging with the corresponding' clutch teeth le upon the inner end of bevel gear the collar being held against the bevel gear by compression spring iid on shaft fl between this collar and pillow block or bearing di. Optionally, a sleeve li may be mounted exteriorly of spring le to protect the same from dust and dirt.

Upon collar 68 is an eye l2 to which previouslymentioned cord 3l is secured, the latter being passed through plastic, porcelain, glass or metal tubular guides "i3, i3 in the wall studs ld, lll above the level of the door frames lil and il, brought over pulleys le and l5, and at the ends connected, as already described, to bolt 2i on the one hand, and to collar te on the other hand, The mentioned tubular guides thus could be replaced by other devices, such as screw eyes or the like, but in any case allow free sliding movement of the cord in either direction through these guides.

Hence, when the opening of door l causes partial rotation of lgears 58 and 52 with consequent rotation of smaller bevel gear 5d and with it the collar 58 and its attaching member or eye 12, the result is that a limited length of oord 3.' is wound up on the collar, drawing the cord toward the right. If the latch bolt 2i at this time projects into latch socket 22 on door` and the latch stud 24 occupies the lower portion of vertical slot 26 in the latch casing, such a pull on cord 3l attached to eye 36 on head 35 of stud 2li will immediately raise the latter in vertical slot portion 26 until the stud is in line slot 25 when the Ibolt will be suddenly withdrawn into the latch casing from door socket 22 by internal spring 29. Thus, opening door l will release the latch of the other door 6, so that both doors are simultaneously opened, but closing the same door l will cause reverse rotation'of the gears by rack t2, again releasing cord 3l and producing a slack thereon which is taken up when manually locking door l by shifting bolt 2! against spring 29 to engage in socket 22 and drawing stud 2e down into vertical slot portion 25. Should the cord be too slack or too tight for proper cooperation between the doors as above described, the collar S8 at the right is seized and pushed toward bearing lll against spring e9 to disengage clutch teeth S9 and 'ill from each other so that the collar may be turned freely forward or backward until the cord is in co1'- rect adjustment, when the collar may be again released so that the spring 4'9 may cause collar teeth 69 to mesh `with teeth l of gear 5b. Both gear Ell and collar 68 may be knurled for improving the grip of the lingers thereon, if desired.

Thus far one-half of the latch-releasing system embodying the invention has been described, but as shown in Figure l, the same system is repeated in reverse so that opening door E will release door l, and vice versa. The second cord 77 passes through hollow guides i8, lil in studs ld, l, being connected to the bolt generally indicated at 19 and adapted to engage in socket 89 in door 'I and be retained in locked position by the bolt stud when engaging in the lower slot portion 8l of the bolt casing. The latch i9 in every respect corresponds to the latch shown and described in connection with Figures 4 and 5, and thus is manually operable to look door l' independently of the latch or operating devices of the other door. Such locking of the door pulls on cord l'l over pulleys 32, 83, and this takes up the slack thereof so that the other end of the cord will be pulled which is attached to and adapted to be opened by the gear-operated releasing device generally indicated at 84 engaging with rack 35 on door The gearing dll and rack 85 are in each detail substantially the same as already illustrated and described in connection with Figures 2 and 3, so that repetition here would be superiiuous.

From the foregoing, it is evident that each door is readily locked by manually locking the latch bolt associated with the door jamb thereof and that either bolt may also be manually released by pushing up the stud thereof when it will snap back and release the door. However, the arrangement is such that whether this is done with one door or the other, the subsequent opening of the unlocked door will initiate operation of its associated gear-operated releasing device and thereby cause corresponding release of thetother door by unlocking the latch boit thereof:` through` the cordinterconnecting the devices.` Inother` words; the. two` latch-release systems are opposite f in arrangement, and: in one sense operated independently of each other, but cooperate in` providing the same ultimaten resultthat unlocking andopening either of two doorsv will automatically release or unlock the other door so that it may be freely opened from outside the room.

Spur and bevel gears,V have been` described: in association and cords mentioned astransferring; the operation originating with these gears to latch bolts for releasing the latter, butit should be understood` that we: may.A use otherV gears, such as spur andcrown gearsin mesh, etc., and chains for transfering the operative movement thereof it desired. It should, of course, beunderstood thatwhen in the foregoing description twodoors` have been named as; cooperating inv such fashion that the opening of" one door automatically releases the latch or` lock. on the other door, the invention is` not limited. to application to only twodoors.

Having. now fully described our invention, we claim:

1. An automatic door latch-releasing system including the combination with two mutually remote doors having individual door jambs spaced a distance apart andadapted tobe independently opened, of a latch means upon the jamb of one door serving to loch` the latter inthe locked position of the latch means, operating means upon the jamb of the other door disposed in eifective position to be actuated by said other door upon opening thereof, and remotely operating transmission means transmitting motion from the operating means to the latchmeansyand releasing the latter and thereby unlocking the firstmentioned door when the other door is opened.

2. An` automatic door latch-release system: including the combination with two doors having individual door jambs and adapted to be independently operated, of a latch casing upon the j amb of one door. having. aiA longitudinally-:slotted portion terminating in a downwardly-directed slotted portion, a latch bolt in the latch casing having a stud projecting therefrom through the longitudinally sloted portion to be accessible for manual locking of-said bolt by shifting the stud down into the downwardly-slotted portion and causing the bolt to project from the jamb into locking engagement with the door, an operating member movably mounted on the jamb of the other door, means on the latter door for actuating the operating member upon opening this other door, a wind-up member rotated by said operating member upon actuation of the latter, a cord connected at one end to the wind-up meniber adapted to be partly wound up thereon when it is rotated, said cord being connected at the other end to the stud on the bolt and raising said stud from the downwardly-directed slotted portion and thereby releasing said stud for movement in the longitudinally slotted portion, thus unlocking the first-mentioned door when the first-mentioned one end of said cord becomes wound partly upon the wind-up member upon opening of said other door, and means for supporting said cord intermediate the two doors for free movement thereof in either direction.

3. An automatic door latch-releasing system including the combination with two doors having independent door jambs and adapted to be individually opened, of a latch casing upon the sition when released from the downwardly-directcd slotted portion, an operating member` movablymounted"V oni each"` door jamb,` means on eachdoor for actuating the respectively adjacent operating member upon opening the door, a` wind-up member associated? with and rotated` by each operating member upon actuation ofi the latter, a pairl ofi cordsf each` individually connected at one' end thereof tothe wind-up membersfandeach adapted to be" partly wound.v up on the respective wind-*up member to which it is connected'. when said wind-up' member is rotated, each cord being connected ati the other end thereof to theV stud on the bolt adjacent to" the respectively-remote door and raising said stud` from the downwardly-directed slotted portion: associated therewith and thereby. releasing said? stud for movement in the longitudinally slotted'` portion, thuslV unlocking the associated.

door, when the other endl ofeachi cord becomes wound: upon the wind-up to which vit is i connected upon opening ofthe` respective other door; and means for supporting bothtcor'ds intermediate thetwoadoors. for free` independent iiflovement` thereofl 4; An` automatic door latch-releasing system including, the: combination with'two doors having.

individual doorjambs spaced apart, said` doors being adapted tobe independently opened, of releasable= latch` means upon the jamb of one door servingtolock the-'latter in the locked position of: the latch; means,.operati-ng means upon` the-jambfofi the other` door includinga gear? rotatablysupportedA in theijamb of the other door, a rack on the latter meshing with the teeth of the gear in closed position of said other door and in a limited portion of its opening and closing movement, a further gear rotatably supported in the latter jamb and in effectiveiposition to be rotated by the first-mentioned gear, a cylindrical portion associated with and rotating with the further gear and serving as a wind-up drum having a cord connected at one end thereto, the other end of the cord being connected to the latch means in effective position to cause releasing of said latch means and thereby the unlocking of the rst-mentioned door upon being pulled by being partly wound up on said cylindrical portion upon opening of said other door, and means for supporting said cord intermediate the two doors and allowing free movement thereof in both directions.

5. An automatic door latch-releasing system including the combination with two doors having individual door jambs spaced apart and said doors being adapted to be independently opened, of releasable latch means upon the jamb of one door serving to lock the latter in the locked position of the latch means, operating means upon the jamb of the other door including a spur gear supported for rotation on a vertical axis in the jamb of the other door, a rack fixed transversely upon the edge of the latter door meshing with the teeth of the spur gear in closed position 0I said other door and in a limited portion of its opening and closing movement, a bevel gear rigidly rotating with said spur gear, a further bevel gear meshing with the first-mentioned .bevel gear and having a substantially horizontal shaft mounted for rotation in the last-mentioned door jamb, clutch means upon the further bevel gear, a cylindrical clutch member slidably mounted on the horizontal shaft and having corresponding clutch means adapted in one position to engage with the clutch means on said further bevel gear, a spring mounted on said horizontal shaft normally tending to maintain the cylindrical -clutch member engaged with the clutch means on said further bevel gear to cause both parts to rotate together, a cord secured at one end to a portion upon the cylindrical clutch means and the other end being connected to the latch means in eiTective position to cause releasing of said latch means and thereby unlocking of the rstmentioned door upon being pulled by being partly wound upon said cylindrical clutch member upon opening of said other door, and means for supporting' said cord intermediate the two doors and allowing free movement thereof in both directions.

6. An automatic door latch-releasing system including the combination with two doors having individual door jambs spaced apart and said doors being adapted to be independently opened, of a latch casing upon the jamb of one door having a longitudinally-slotted portion terminating in a downwardly-directed slotted portion, a latch bolt mounted in the latch casing having a stud projecting therefrom through the longitudinally slotted portion to be accessible for manually locking said bolt by shifting the stud down into the downwardly-slotted portion and causing the bolt to project from the jamb into locking engagement with the door, a spring in said latch casing tending to return said bolt into released withdrawn position, operating means upon the jamb of the other door including a gear rotatably supported in the jamb of the other door upon a shaft adapting it for rotation on a vertical axis, a rack fixed transversely upon the edge of the latter door and meshing with the teeth of the gear in closed position of said other door and in a limited portion of its opening and closing movement, a bevel gear rigidly rotating with said first-mentioned gear, a further bevel gear meshing with the first-mentioned bevel gear and having a substantially horizontal shaft mounted for rotation in the last-mentioned door jamb, clutch means upon the further bevel gear, a cylindrical clutch member slidably mounted on the horizontal shaft and having corresponding clutch means adapted in one position to engage with the clutch means on said further bevel gear, a spring mounted on said horizontal shaft tending normally to maintain the cylindrical clutch member engaged with the clutch means on said further bevel gear, a cord secured at one end to a portion upon the cylindrical clutch member and at the other end being connected to the latch means in eiective position to cause releasing of said latch means and thereby the unlocking of the iirst-mentioned door upon being pulled by being partly wound upon said cylindrical clutch member on opening of said other door, and means for supporting said cord intermediate the two doors including a plurality of supportV members.

MICHAEL L. THOMAS, SR. MTCHAEL L. THOMAS, JR.

REFERENCE S CETED The following references are of record in the file oi this patent:

UNTTED STATES PATENTS 

